Medicines containing pseudoephedrine are expected to be available over the counter again next year, ACT leader David Seymour says.

David, appointed Associate Health Minister with responsibility for Pharmac and championing the party's policy to return the drug to pharmacies, is expected to introduce legislation for it on Tuesday.

This would reclassify pseudoephedrine from a restricted medicine, which would allow the public to purchase it from a pharmacy without a prescription.

It would still be subject to some restrictions: It would only be available for purchase directly from a pharmacist, and restrictions on importing and exporting of the drug would remain.

David says the drug was banned because of fears it would be used to produce methamphetamine.

"The reality is that the gangs have far more effective ways of obtaining pseudoephedrine to manufacture methamphetamine and we should tackle these head on instead.

"Alternative cold and flu medicines have been shown to be no more effective than a placebo. New Zealanders are being denied decent cold and flu medication, but the gangs are selling more methamphetamine than ever.

"The current law isn't working and that's why the government is acting."

He says pharmaceutical companies would need to apply for product approval in New Zealand, but Medsafe was using an expedited process to approve the medicine as quickly as possible.

"Taking into account supply chains and the ability for companies to prepare products, it is expected the medication will be back on shelves in 2025," he says.